[INFO] updating cached repository Bkindmonk/RustPractice
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Bkindmonk/RustPractice
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Bkindmonk/RustPractice" "work/ex/beta-1.38-1/sources/1.37.0/gh/Bkindmonk/RustPractice"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/Bkindmonk/RustPractice'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Bkindmonk/RustPractice" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Bkindmonk/RustPractice"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Bkindmonk/RustPractice'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] dddc1c842ad316fb93f1f4a3a9741aea4ff490c9
[INFO] sha for GitHub repo Bkindmonk/RustPractice: dddc1c842ad316fb93f1f4a3a9741aea4ff490c9
[INFO] validating manifest of Bkindmonk/RustPractice on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of Bkindmonk/RustPractice on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing Bkindmonk/RustPractice
[INFO] finished frobbing Bkindmonk/RustPractice
[INFO] frobbed toml for Bkindmonk/RustPractice written to work/ex/beta-1.38-1/sources/1.37.0/gh/Bkindmonk/RustPractice/Cargo.toml
[INFO] started frobbing Bkindmonk/RustPractice
[INFO] finished frobbing Bkindmonk/RustPractice
[INFO] frobbed toml for Bkindmonk/RustPractice written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Bkindmonk/RustPractice/Cargo.toml
[INFO] crate Bkindmonk/RustPractice already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing Bkindmonk/RustPractice against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/Bkindmonk/RustPractice:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 88ba42db0aaf8c22d899638bae1da559115283eb347797f2495d3c3fbee67324
[INFO] running `"docker" "start" "-a" "88ba42db0aaf8c22d899638bae1da559115283eb347797f2495d3c3fbee67324"`
[INFO] [stderr]    Compiling mergesort v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:91:13
[INFO] [stderr]    |
[INFO] [stderr] 91 |         let mut realhalves = (*real).split_at_mut(halflength);
[INFO] [stderr]    |             ----^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:92:13
[INFO] [stderr]    |
[INFO] [stderr] 92 |         let mut scratchhalves = (*scratch).split_at_mut(halflength);
[INFO] [stderr]    |             ----^^^^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.16s
[INFO] running `"docker" "inspect" "88ba42db0aaf8c22d899638bae1da559115283eb347797f2495d3c3fbee67324"`
[INFO] running `"docker" "rm" "-f" "88ba42db0aaf8c22d899638bae1da559115283eb347797f2495d3c3fbee67324"`
[INFO] [stdout] 88ba42db0aaf8c22d899638bae1da559115283eb347797f2495d3c3fbee67324
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/Bkindmonk/RustPractice:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] 0a12bd24391486b9b3a58cdc077878fb89e689a6ce44d5ac06e552b13fc9e131
[INFO] running `"docker" "start" "-a" "0a12bd24391486b9b3a58cdc077878fb89e689a6ce44d5ac06e552b13fc9e131"`
[INFO] [stderr]    Compiling mergesort v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:91:13
[INFO] [stderr]    |
[INFO] [stderr] 91 |         let mut realhalves = (*real).split_at_mut(halflength);
[INFO] [stderr]    |             ----^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:92:13
[INFO] [stderr]    |
[INFO] [stderr] 92 |         let mut scratchhalves = (*scratch).split_at_mut(halflength);
[INFO] [stderr]    |             ----^^^^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.77s
[INFO] running `"docker" "inspect" "0a12bd24391486b9b3a58cdc077878fb89e689a6ce44d5ac06e552b13fc9e131"`
[INFO] running `"docker" "rm" "-f" "0a12bd24391486b9b3a58cdc077878fb89e689a6ce44d5ac06e552b13fc9e131"`
[INFO] [stdout] 0a12bd24391486b9b3a58cdc077878fb89e689a6ce44d5ac06e552b13fc9e131
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/Bkindmonk/RustPractice:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "test" "--frozen"`
[INFO] [stdout] 94891ed37927188089d8b2657b5e141a48d67c5002f1877fcd57b79dd8d7a1e6
[INFO] running `"docker" "start" "-a" "94891ed37927188089d8b2657b5e141a48d67c5002f1877fcd57b79dd8d7a1e6"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/mergesort-98f66f1d938dee50
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "94891ed37927188089d8b2657b5e141a48d67c5002f1877fcd57b79dd8d7a1e6"`
[INFO] running `"docker" "rm" "-f" "94891ed37927188089d8b2657b5e141a48d67c5002f1877fcd57b79dd8d7a1e6"`
[INFO] [stdout] 94891ed37927188089d8b2657b5e141a48d67c5002f1877fcd57b79dd8d7a1e6